Wheel disk and method of manufacture



E. WILL! WHEEL 'DISK AND METHOD OF MANUFACTURE Filed Au 1, 19

mmmm V m I wzfmejs Patented Nov. 29, 1927.

WILLIAM ERASTUS WILLIAMS, F WILMETTE, ILLINOIS, ASSIGNOR, BY MESNE AS- BIGWN'IS, TO STEEL WHEEL GORPORATION, OF LANSING, MICHIGAN, A COR- JPOBA'IION OF MICHIGAN.

WHEEL DISK IAN!) METHOD OF MANUFACTURE.

Application filed August 1, 1922. Serial No. 579,018.

My invention relates to a method of making true symmetrical disks, for disk wheels for automobiles, and the object of the invention is to provide means for forming with dies ta ered disks into true symmetrical shapes uslng disks that vary in thicknesses. Reference will be had to the accompanying drawing in which Figure 1 is a transverse section of a finished disk. 7

Figure 2 is a section through a finished blank, ready for pressing, but on a distorted scale to better show variations in thicknesses.

Fi re 3 is a diametrical section through the ies, in position at the completion of the pressing operation.

Figure 4 shows an old style disk in section.

Figure 5 is a plan view of an old style disk, showing the defects in the pressing due to the variations in the thickness of the disk blank.

Figure 6 is a section on line 6-6 of Figure 5.

In the manufacture of steel disk wheels for automobiles, the most desirable form is to have a metal disk which is thicker around the hub zone and thinner around the margin, and circular disks of this type are difiicult to produce in exact sizes either by rolling or by other means, without serious extra cost.

In rolling a tapered disk the metal will draw unevenly down the taper and thus commercial disks, (and by commercialI mean disks that a rolling mill will be able to produce in quantity production, with the same average care and tolerances as with other rolling mill products), will so vary in thickness as to make a smooth pressing in dies almost impossible on a quantity production basis, in the forms generally heretofore use for tapered disk wheels.

In Figure 2, 1 indicates in full lines, the exact form of disk desired and the dotted lines 2, 3 indicate the variations that actually occur in commercially rolled disks.

When commercially produced tapered blanks are dicated in ig. 4, that is into a form having broad smooth areas, small buckling irregu- M larities, indicated at 5, Fig. 6, cannot readily be avoided. Practically, steel dies cannot exactly fit both faces of blanks varyin in thickness as indicated by the dotted es pressed into such form as that in-' 2, 3, of Fig. 2, and when it is sought to produce from such blanks forms analogous to that of Fig. 4. many of the disks produced will have buckled areas such as shown at 5, Fig. 6. These, practically, must be hammered out or ground out, or such disks must ous with a similar reversed rid e or reentrant region, so that each face 0 the disk has concentric annular waves or corrugations. The dies 11', 12, Fig. 3, which so form the blanks, are not made with concave and convex areas exactly correspondin to a perfect disk made from a perfect blan r, but

each die has its re-entrant annular areas formed with a clearance or excess depth, as is shown at 8, 10 of one die and at 9 of the other. If the commercial blank having slight irregularities, as suggested in Fig. 2, be placed in such dies, the salient portions of each die will force the metal into the corresponding re-entrantv portions of its companion, and under die action the metal of such irregular blank willbe properly distributed, any excess entering the clearance spaces. The disks produced will have smooth surfaces free from buckled areas. The clearances may be very slight, and the disks produced will approach very closely the form of the theoretical disk of Fig. 1,- no matter whether the blank had in any region a slight excess or a small deficiency of metal.

What I claim is: 1. A disk body for vehicle wheels having an outwardly tapering radial cross section and presenting between the hub and rim areas a concentric series of concave and convex zones, adjacent zones merging gradually into each other on an ogee curve and decreasing in depth radially outward, the'curves flattening as the thickness of the disk decreases.

2. The method of forming wheel disks from commercial, circular metal blanks of outwardly tapered radial section, which consists in pressing the blanks between annularly corrugated co-acting dies each having the depth of its re-entrant areas greater than the projection of the co-acting salient areas of its companion, forming clearance spaces coincident with the salent annuli on each face of the blank to be formed.

3. The method of forming wheel disks radial sections of which are outwardly tapered, which consists in pressing a plate of such cross section between co-acting dies each having annular ridges to enter corresponding depressions of its companion, the corresgonding salient and re-entrant areas only aving slight clearance spaces, whereby portions of a sli htly irregular blank may be drawn over t e-salient portions while not gripped at these points and the metal be properly distributed without bucklin 4. The method of forming whee? disks from circular plates, which consists in shaping the plates between dies each having salient and re-entrant portions adapted to co-act with reverse portions of the other, there being clearance spaceat the bottom of each re-entrant area to permit the flow into said clearance spaces of excess metal from adjacent portions of said disks.

Si ed at Chicago in the county of Cook and gtate of Illinois, this 13th day of July, 1922.

WILLIAM ERASTUS WILLIAMS. 

